I currently have a Sta-Rite SR400NA heater. It has been going for 11 yrs and the blower motor has died on it. I have been recommend by many not to repair it but rather replace the unit as this might be the beginning of problems for the heater. I have a lot of chose in the unit I put in. I am tempted to keep the old one as spare parts and replace it for a like heater. Does any one have recommendations? Do I need (the old one was not) CuproNickle heat exchanger? Given that Sta-Rite was purchased should I be looking else where? are there heaters / types you would recommend. I am all ears.